The Spy Cables are one of the most wide-ranging leaks of intelligence papers ever, taking us into the world of espionage Al Jazeera's Investigative Unit, in collaboration with The Guardian newspaper, is publishing a selection of "top-secret" documents, and exploring the stories within them

A digital leak to Al Jazeera of hundreds of secret intelligence documents from the world's spy agencies has offered an unprecedented insight into operational dealings of the shadowy and highly politicised realm of global espionage.

Spanning a period from 2006 until December 2014, they include detailed briefings and internal analyses written by operatives of South Africa's State Security Agency (SSA). They also reveal the South Africans' secret correspondence with the US intelligence agency, the CIA, Britain's MI6, Israel's Mossad, Russia's FSB and Iran's operatives, as well as dozens of other services from Asia to the Middle East and Africa.

Among the revelations, the Spy Cables disclose how:

Israel's Mossad told its allies that Iran was not working to produce nuclear weapons just a month after Prime Minister Benjamin Netanyahu warned it was barely a year from being able to do so;

The CIA made attempts to contact Hamas directly despite the US government listing the Palestinian group as a "terrorist organisation";

Britain's MI6 sought South African help in an operation to recruit a North Korean official who had previously refused their cash; and

South African and Ethiopian spies struggled to "neutralise" an assassination plot targeting a leading African diplomat.

The files unveil details of how, as the post-apartheid South African state grappled with the challenges of forging new security services, the country became vulnerable to foreign espionage and inundated with warnings related to the US-"War on Terror".

Following the 9/11 attacks, South African spies were flooded with requests related to al-Qaeda, despite their own intelligence gathering and analysis telling them that they faced minimal direct threats from such groups, and that the main threat of violence on South African soil came from domestic far-right groups.

The South Africans' focus on Iran was largely a result of -pressure from other nations, and the leaked documents also report in depth on alleged efforts by Iran to defeat international sanctions and even its use of Persian rug stores as front companies for spying activity.-

'HUMINT'

Unlike the Edward Snowden documents that focus on electronic signals intelligence, commonly referred to in intelligence circles as "SIGINT", the Spy Cables deal with human intelligence, or "HUMINT".

Rather than chronicling spy-movie style tales of- ruthless efficiency of intelligence agencies, they offer an unprecedented glimpse into the daily working lives of people whose jobs are kept secret from the public.

It has not been easy to decide which Spy Cables to publish, and hundreds will not be revealed.

After verifying the cables, we had to consider whether the publication of each document served the public interest, in consultation with industry experts, lawyers, and our partners at The Guardian. Regardless of any advice received, the decision to publish has been Al Jazeera's alone.

We believe it is important to achieve greater transparency in the field of intelligence. The events of the last decade have shown that there has been inadequate scrutiny on the activities of agencies around the world. That has allowed some to act outside their own laws and, in some cases international law.

Publishing these documents, including operational and tradecraft details, is a necessary contribution to a greater public scrutiny of their activities.

The Spy Cables also reveal that in many cases, intelligence agencies are over-classifying information and hiding behind an unnecessary veil of secrecy. This harms the ability of a democratic society to either consent to the activities of their intelligence agencies or provide adequate checks and balances to their powers.

The Spy Cables are filled with the names, personal details, and pseudonyms of active foreign intelligence operatives who work undercover for the dozens of global spy agencies referenced in the files.

We confronted the possibility that publishing identities revealed in the cables could result in harm to potentially innocent people. We agreed that publishing the names of undercover agents would pose a substantial risk to potentially unwitting individuals from around the world who had associated with these agents.

We believe we can most responsibly accomplish our goal of achieving greater transparency without revealing the identities of undercover operatives.

For these reasons, we have redacted their names. We have also redacted sections that could pose a threat to the public, such as specific chemical formulae to build explosive devices.

Finally, some of the Spy Cables have been saved for future broadcast - ones that needed further contextualisation. Regardless of when we publish, the same considerations will inform our decisions over what to redact.